1. Technical Field
The present invention relates to an illumination device and a projector.
2. Related Art
In the past, as an illumination device used for a projector, there has been known an illumination device having a light source device for emitting the excitation light (blue light), and a rotating fluorescent plate obtained by providing three segment areas to a circular disk, which can be rotated by an electric motor, and is provided with two types of fluorescent layers emitting light beams with respective colors different from each other (a red light beam and a green light beam) respectively in the two segment areas thereof (see, e.g., JP-A-2009-277516). It should be noted that the remaining segment area out of the three segment areas provided with no fluorescent layer is provided with a scattering layer for scattering the excitation light (the blue light) at a predetermined scattering intensity.
According to the illumination device of the related art, it becomes possible to obtain a plurality of colored light beams (the red light beam, the green light beam, and the blue light beam) using the light source device for emitting the excitation light.
However, in the illumination device of the related art, since the two types of fluorescent layers need to be formed on the circular disk, there arises a problem that the manufacturing process of the rotating fluorescent plate becomes complicated.
Further, in the illumination device of the related art, since the types of the colored light beams emitted from the illumination device are sequentially switched at high rate in accordance with the rotation of the rotating fluorescent plate, there exists a problem that it is difficult to apply the illumination device to the liquid crystal projector “of a non-color sequential type having a strong characteristic of being capable of projecting a gentle image with no color breakup phenomenon and being capable of performing fine gradation expression to thereby be capable of projecting a natural image.”